| 摘要 |
<p>The apparatus includes a housing in which a frame is rotationally mounted, an instrument which is pivotally mounted about two axes within said frame, level sensing devices on the instrument to detect the tilt of the instrument about said two axes, and means for tilting the instrument within the frame so that the instrument's reference axis may be brought to a substantially vertical position when the apparatus is within an inclined well bore. The instrument is mounted unsymmetrically within the frame so that the instrument may be tilted in one direction on one axis a much greater amount than on the other axis and in the other direction. The method steps include the steps of detecting the level position of the instrument along the two axes, rotating the frame within the housing to orient the instrument so that its large range tilt capacity is brought into position to correct the tilt of the instrument and tilting the instrument within the frame to bring the reference axis of the instrument to a substantially vertical position.</p> |
